chore(knip): add config and remove dead code/deps

- knip.json: scope to src, ignore submodule/worktrees, mark
  generated abi.ts as unresolved-allowed, honor @public JSDoc tag
- drop 14 orphaned files (12 ui components, model/Bank, model/Pix)
- drop 18 unused deps (urql, tanstack, wagmi/{core,vue}, graphql,
  permissionless, graphql-codegen suite, axe-core, lighthouse,
  vue/test-utils)
- drop 4 unused exports and de-export 9 internal-only types
- mark NetworksTestnet as @public (in-flight testnet support)

src/config/networks.ts

@@ -29,6 +29,7 @@ export const Networks: { [key: string]: NetworkConfig } = {
   },
 };
 
+/** @public */
 export const NetworksTestnet: { [key: string]: NetworkConfig } = {
   sepolia: {
     ...sepolia,